Neomycin
MYCIFRADIN
Pronunciation: nee-oe-MYE-sin
“New Mice afraid in (there)”
"-fradin" reference the source organism, Streptomyces fradiae
What it isAminoglycoside inhibiting the 30S ribosomal subunit; topical use and gut decontamination.
Why this oneMinimal oral absorption lets it act on gut flora, which is how it is used before colorectal surgery and in encephalopathy.
What limits itThe small absorbed fraction is still nephrotoxic and ototoxic in renal impairment. It is a common cause of contact dermatitis.
FDA-approved for
- hepatic encephalopathy adjunct and bowel preparation
- topical infection
FDA label
Read the full label on DailyMed ↗
| FDA dosing | Population | Start | Target | Max |
|---|---|---|---|---|
| Hepatic coma (adjunct) | Adults | 4–12 g/day in divided doses ×5–6 days | up to 4 g/day for chronic hepatic insufficiency | 12 g/day |
| Preoperative bowel prep (elective colorectal surgery) | Adults | 1 g (with erythromycin 1 g) at 1 pm, 2 pm, and 11 pm pre-op day 1 | per regimen | per regimen |
Renal Increased nephro/oto/neurotoxicity risk in renal impairment; monitor renal function and neomycin serum levels
Hepatic Undefined
Do not exceed 2 weeks of therapy
Instructions
- Use lowest possible dose for shortest period
- Treatment longer than 2 weeks is not recommended
- Monitor renal function, audiometric/vestibular tests, and neomycin serum concentrations
Available strengths
- tab 500 mg
- granules 100 kg/100 kg
- ointment 0.5 g/100 g
- ointment 3.5, 5 mg/g
Contraindications
- Intestinal obstruction
- Inflammatory or ulcerative GI disease (enhanced GI absorption)
- Cross-sensitivity with other aminoglycosides
Cautions
- Neurotoxicity/ototoxicity — often delayed, may be permanent (bilateral auditory, sometimes vestibular)
- Nephrotoxicity
- Neuromuscular blockade and respiratory paralysis (esp. with anesthetics/NMBAs, massive citrate-blood transfusion)
- Additive toxicity with other aminoglycosides and nephro/neurotoxic drugs; avoid potent diuretics
- Malabsorption syndrome with prolonged therapy
Adverse reactions
- Nausea
- Vomiting
- Diarrhea
- Malabsorption syndrome
- Nephrotoxicity
- Ototoxicity
- Neuromuscular blockade
Pregnancy Undefined (refer to systemic-toxicity warnings)
Lactation Undefined
Cost
| Strength | #/mo | generic $/unit | CostPlus | |
|---|---|---|---|---|
| 500 mg | tab | per unit | $0.83/ea | out of stock |
Generic entry2002
⚠ BOXED WARNINGS
- Nephrotoxicity and ototoxicity
- Neuromuscular blockade and respiratory paralysis
Classes and tags
Clinical profile
Legacy pregnancy categoryD
Defining liabilityNephrotoxicity and often irreversible ototoxicity require renal and concentration monitoring.
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